They will usually refund you if you end up getting charged because you forgot to cancel. It isn't worth the headache of a chargeback.

Plus they have to pay a fee for chargebacks regardless of whether they think it's valid or not, so strong disincentive.

Funny, I got a fraud call recently because CrunchyRoll decided to try to renew a subscription I abandoned years ago and the card they have is expired.

I know it wasn't me because I gave up entirely on the service after they changed something about their login systems to reject my password and I could no longer get in. Support wanted me to jump through a lot of hoops and I just refused, choosing instead to just stop doing business there because I wasn't really watching anything at that point anyway.

This was around 2022, mind you, so they tried to renew me after several years with no explanation.

It's way easier to just not give them a way they can charge you. That way you don't have to deal with a support representative fakely asking you how your weekend was, and who doesn't actually care about your weekend.